The invention relates to a 0.degree.-180.degree. active phase shifter for microwave frequencies.
A known phase shifter of this type embodies a differential shape comprising two field effect transistors whose sources are coupled together and which are charged by an impedance Z whose value is adjusted to obtain equality in the magnitude of the signals present at the drains of the transistors, and to obtain the desired value of the phase, i.e. 180.degree..
Such an adjustment can only be realized in a relatively small frequency band and, moreover, it occupies a considerable part of the surface of the substrate when it is integrated.